[(0,1),(1,2),(0,2),(2,3),(1,4),(4,5),(3,6),(5,6),(3,7),(6,8),(7,9),(7,10),(4,11),(5,12)]
[(0,1),(1,2),(0,3),(1,3),(2,4),(3,4),(4,5),(2,6),(6,7),(7,8),(7,9),(6,10),(5,11),(5,12)]
